The present invention is directed to a dental handpiece comprising means for forming a compatible connection of the handpiece to differently designed rotating joints which deliver different supply media, such as air, water, electrical power and light, and which rotating joints offer these supply media at different locations, said rotating joints being permanently or detachably connectable to a supply hose.
Examples of the various handpieces can be handpieces which are a turbine handpiece, a handpiece which has an air or electrical motor, a handpiece which is a sprayer handpiece or a handpiece for removing dental calculus.
U.S. Pat. No. 4,080,737, whose disclosure is incorporated by reference and which was based on German Patent Application 25 49 177, discloses a coupling mechanism which, in one embodiment, is constructed as a rotating joint. Various handpieces can be operationally coupled to and uncoupled from this rotating joint without the assistance of tools. Voltage or, respectively, light is also offered at the coupling location, in addition to the agents of air and water. A light-conducting element in the form of a light guide is arranged in the center of the joint and a light-forwarding element in the form of an additional light guide is arranged at the end face of the handpiece for transmitting light through the handpiece. When the handpiece and rotating joint are in their coupled condition, the ends of the two light guides are arranged correspondingly opposite one another.
U.S. Pat. No. 4,655,709, whose disclosure is incorporated by reference and which was based on German Application 34 31 052, discloses a coupling mechanism that reveals a possibility of being able to connect turbine handpieces to a rotating joint, wherein both the turbine handpieces have integrated lamps as well as two turbine handpieces having a lamp arranged in the rotating joint. The rotating joint has a peg-shaped or pin-shaped coupling member that is engaged into a correspondingly fashioned receptacle sleeve or socket of the handpiece to form the coupling, which will transfer both the cooling means as well as drive means between the two units. In order to transfer the voltage for feeding the electrical lamp, the rotating joint contains a contact arrangement which has wiper contacts including bands or contact points on the peg-shaped coupling member, which are engaged by terminal contacts of a lamp arranged in the handpiece attachable to the coupling member or the contacts of a lamp arranged in the coupling member or sleeve of the joint.
One advantage of this coupling mechanism is that the turbine handpiece with an integrated lamp, as well as with an externally arranged lamp, can be alternately connectable to one in the same rotating joint, whereby the use of the handpiece can itself easily undertake the replacement of the lamp with a plug-in connection and vice-versa. Since the turbine handpieces are structurally matched to the one rotating joint, it is consequently not possible in the prior art to couple these handpieces to rotating joints that are fashioned with different dimensions.